diff options
| author | Jean-Marc Valin <jmvalin@amazon.com> | 2022-07-24 03:46:16 -0400 |
|---|---|---|
| committer | Jean-Marc Valin <jmvalin@amazon.com> | 2022-07-24 03:46:16 -0400 |
| commit | ab04fbb1b7d0b727636d28fc2cadb5df9febe515 (patch) | |
| tree | 537fa3cda0461104831fabf3e017a59a4032d83e | |
| parent | fd9c0f1e1f1b74c46c5872217e3289a9edf69d48 (diff) | |
| download | opus-ab04fbb1b7d0b727636d28fc2cadb5df9febe515.tar.gz | |
Smooth out the LBRR rate estimate
Reduces fluctuations in the non-FEC target bitrate.
| -rw-r--r-- | silk/enc_API.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/silk/enc_API.c b/silk/enc_API.c index 55a33f37..548e0736 100644 --- a/silk/enc_API.c +++ b/silk/enc_API.c @@ -270,6 +270,7 @@ opus_int silk_Encode( /* O Returns error co psEnc->state_Fxx[ 0 ].sCmn.fs_kHz * 1000 ); ALLOC( buf, nSamplesFromInputMax, opus_int16 ); while( 1 ) { + int curr_nBitsUsedLBRR = 0; nSamplesToBuffer = psEnc->state_Fxx[ 0 ].sCmn.frame_length - psEnc->state_Fxx[ 0 ].sCmn.inputBufIx; nSamplesToBuffer = silk_min( nSamplesToBuffer, nSamplesToBufferMax ); nSamplesFromInput = silk_DIV32_16( nSamplesToBuffer * psEnc->state_Fxx[ 0 ].sCmn.API_fs_Hz, psEnc->state_Fxx[ 0 ].sCmn.fs_kHz * 1000 ); @@ -342,6 +343,7 @@ opus_int silk_Encode( /* O Returns error co opus_uint8 iCDF[ 2 ] = { 0, 0 }; iCDF[ 0 ] = 256 - silk_RSHIFT( 256, ( psEnc->state_Fxx[ 0 ].sCmn.nFramesPerPacket + 1 ) * encControl->nChannelsInternal ); ec_enc_icdf( psRangeEnc, 0, iCDF, 8 ); + curr_nBitsUsedLBRR = ec_tell( psRangeEnc ); /* Encode any LBRR data from previous packet */ /* Encode LBRR flags */ @@ -386,8 +388,7 @@ opus_int silk_Encode( /* O Returns error co for( n = 0; n < encControl->nChannelsInternal; n++ ) { silk_memset( psEnc->state_Fxx[ n ].sCmn.LBRR_flags, 0, sizeof( psEnc->state_Fxx[ n ].sCmn.LBRR_flags ) ); } - - psEnc->nBitsUsedLBRR = ec_tell( psRangeEnc ); + curr_nBitsUsedLBRR = ec_tell( psRangeEnc ) - curr_nBitsUsedLBRR; } silk_HP_variable_cutoff( psEnc->state_Fxx ); @@ -396,6 +397,16 @@ opus_int silk_Encode( /* O Returns error co nBits = silk_DIV32_16( silk_MUL( encControl->bitRate, encControl->payloadSize_ms ), 1000 ); /* Subtract bits used for LBRR */ if( !prefillFlag ) { + /* psEnc->nBitsUsedLBRR is an exponential moving average of the LBRR usage, + except that for the first LBRR frame it does no averaging and for the first + frame after after LBRR, it goes back to zero immediately. */ + if ( curr_nBitsUsedLBRR < 10 ) { + psEnc->nBitsUsedLBRR = 0; + } else if ( psEnc->nBitsUsedLBRR < 10) { + psEnc->nBitsUsedLBRR = curr_nBitsUsedLBRR; + } else { + psEnc->nBitsUsedLBRR = ( psEnc->nBitsUsedLBRR + curr_nBitsUsedLBRR ) / 2; + } nBits -= psEnc->nBitsUsedLBRR; } /* Divide by number of uncoded frames left in packet */ |